NAV Return

The change in the net asset value of an exchange-traded fund (ETF) or mutual fund over a given time period. The NAV return of an ETF or mutual fund can be different than the total return that investors realize because these products can trade at a premium or discount to the price of the fund and to the value of the assets held in the portfolio.

Investopedia Says:
Many investors will monitor the NAV return instead of total return. It is a better measure of comparing the relative performance of several funds because it ignores the market forces that can cause some funds to trade at a premium or discount to their net asset values.

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